The Last Polar Bears by Harry Horse - old paperback
Grandfather is off on an expedition to the North Pole to find the Last Polar Bears. With him goes Roo - a dog of character and strong views - and a golf-bag full of their equipment. The intrepid explorers set sail on the good ship Unsinkable and embark on the adventure of a lifetime.
Eccentric, moving and immensely funny, their story is told through a series of extraordinary letters.